Plastic plugs for use in concrete forms

ABSTRACT

A plastic plug for use with a tie bar of concrete wall forms which is made of a plastic frustoconical body having an outer larger end intended to be applied against the inner surface of a form panel and having an inner smaller end that is embedded in the concrete of the wall. The plastic body is formed on the inside with a longitudinal through passage having a shape and size to slidably and snugly receive one end of a tie bar. The inner end of the body is closed but for the opening created by the passage so as to prevent entry of concrete inside the body. The outer end of the body has a circumferential sealing flange intended to be applied against the inner surface of a form panel to prevent entry of concrete inside the plug body. In combination with this plug, a flat tie bar for holding concrete form panels in position and formed at one end with a pair of notches each provided along one of the two edges of the bar and opposite one another. A resilient ring pressed into the notches for abutment by the plug, said notches and ring being spaced from the end of the bar a distance such that the plug outer surface and the sealing flange may be slightly pressed, in use against the inner surface of a form panel.

United States Patent Brosseau 1 Feb. 22, 1972 [54] PLASTIC PLUGS FOR USEIN [73] Assignee: Formex Ltd., Cite Jacques-Cartier,

Quebec, Canada [22] Filed: Aug. 15, 1969 [21] App1.No.: 850,493

All

Primary Examiner-Robert D. Baldwin Assistant Examiner-Dewalden W. JonesAttorney-Raymond A. Robic [57] ABSTRACT A plastic plug for use with atie bar of concrete wall forms which is made of a plastic frustoconicalbody having an outer larger end intended to be applied against the innersurface of a form panel and having an inner smaller end that is embeddedin the concrete of the wall. The plastic body is formed on the insidewith a longitudinal through passage having a shape and size to slidablyand snugly receive one end of a tie bar. The inner end of the body isclosed but for the opening created by the passage so as to prevent entryof concrete inside the body. The outer end of the body has acircumferential sealing flange intended to be applied against the innersurface of a form panel to prevent entry of concrete inside the plugbody.

In combination with this plug, a flat tie bar for holding concrete formpanels in position and formed at one end with a pair of notches eachprovided along one of the two edges of the bar and opposite one another.A resilient ring pressed into the notches for abutment by the plug, saidnotches and ring being spaced from the end of the bar a distance suchthat the plug outer surface and the sealing flange may be slightlypressed, in use against the inner surface of a form panel.

2 Claims, 9 Drawing Figures 'PATENIEDFEB 22 m2 SHEET 1 BF 2 I NVENTORLouis Philippe B I EAU I A TTORNE Y mamsnrfim 2 SHEET 2 OF 2 INVEN T ORLouis Philippe BROSSEAU ATTORNEY PLASTIC PLUGS FOR USE IN CONCRETE FORMSThe present invention relates to plastic plugs for plugging face holesmade by tie bars joining facing panels defining forms for use in makingconcrete walls or the like.

Face holes in concrete walls are presently plugged by wooden plugs whichpresent many disadvantages particularly when flat tie bars are used inconcrete forms such as of the type disclosed in my prior Canadianpatents No. 588,509 of Dec. 8, 1959; 798,239 of Nov. 5, 1968 and US.Pat. No. 3,414,230 ofDec. 3, 1968.

There are indeed several difficulties inherent to the use of woodenplugs. Once they are put on the tie bars, they do not easily stay intheir proper locations, that is in abutment against the inner surfacesof the form panels. Also, because the openings through which the tiebars extend are cylindrical and the tie bars are flat, concrete easilyflows into the plug bores from both ends, particularly during vibrationof the concrete. Thus, after setting, this concrete inside the plugsmust be broken up with a chisel before the plugs can be removed. It caneasily be seen that the use of such wooden plugs is expensive and nonetoo satisfactory.

The present invention overcomes these difficulties by providing plugsmade of plastic material and each having a frustoconical body formedwith an inner guide means defining a longitudinal passage of a size andshape to allow the plug to be slidably and snugly displaceable on a tiebar. In this manner, the inner end of the body is closed but for theopening created by this passage and thus the entry of concrete insidethe body is prevented.

Additionally and preferably, the plug has a circumferential sealingflange at the larger end of the body, this flange having a flat faceintended to be applied against the inner surface of the concrete form toprevent entry of concrete inside the plug by that end.

In order to keep such plugs in proper position on the tie bars, they arepreferably used with tie bars formed at each end with a pair of notcheseach along one of the two edges of the bar and opposite one another, aresilient ring being pressed into these notches for abutment by thesmaller end of the plug. This particular feature will ensure that theplastic plugs of the invention will not untimely move along the tie barswhen used. Also, the resilient rings are so positioned on the bars as toslightly press the plastic plugs against the inner surface of the formpanel to ensure proper sealing of the larger ends of the plugs againstthe said inner surface.

A better understanding of the invention will be afforded by thefollowing description having reference to the appended drawings wherein:

FIG. I is a perspective and cross-sectional view of a portion of aconcrete form illustrating the use of the plastic plugs of the inventionand the improved tie bar and resilient rings;

FIG. 2 is a side elevation view, one plug being shown in cross section,of the plug and bar combination according to the invention;

FIG. 3 is a cross-sectional view along line 3-3 of FIG. 1;

FIG. 4 is a perspective view of a plug-removing tool shown while beinginserted inside a plastic plug according to the invention;

FIG. 5 is a side elevation and cross-sectional view of the tool and partof a concrete work, similar to the view of FIG. 4;

FIG. 6 is a cross-sectional view along line 6-6 of FIG. 5;

FIG. 7 is a perspective view, on a larger scale, of a concrete face holewith a decorative cap about to be inserted into the face hole;

FIG. 8 is a perspective view of a concrete work with face holes obtainedby means of plastic plugs according to the invention;

FIG. 9 is a perspective view, on a larger scale, of the portion of FIG.8 circumscribed by a rectangle made by broken lines.

The present invention is illustrated in FIG. I in use with concreteforms of the type illustrated and disclosed in my previous patentslisted above. Such forms include a series of panels I fixed to boundaryframe members 3 by means of rivets or the like, not shown. A boundaryframe member 3 normally stands in abutment with a similar boundary frameof an adjacent panel and the two are held together by means of a seriesof lock plates 5 extending successively through the slots 5 7 and 9 ofthe boundary frame member 3 and tie bars 11, respectively, as well asthrough similar slots of the adjacent boundary frame member. Theassemblies are locked into position by means of wedges (not shown)extending through slots 13 of the lock plates 5.

As clearly illustrated in FIGS. 1 and 2, the plugs I5 of the inventionare slid over the tie bars 11 in the assembly of the forms prior topouring of the concrete.

The plug 15 of the invention has a frustoconical body having an outerlarger end 17 applied against the inner surface of the form panel 1 andan inner smaller end web 19 embedded in the concrete of wall 21. Plug 15is made entirely of plastic material and is molded with inner guidemeans defining a longitudinal passage extending completely through theplug, this passage being of a shape and size to allow plug 15 to beslidably and snugly displaceable on tie bar 11. The inner end 19 of thebody is closed but for the opening created by this passage thuspreventing entry of concrete inside the body.

The plug body is formed with a tapered bore 25 and the aforementionedguide means are formed by ribs 27 extending diametrically opposite oneanother inwardly of bore 25 and formed along the inner edges thereofwith guide ways providing the said passage 23 for engagement by theedges of the tie bar 1 l as clearly shown in FIG. 3.

The outer end 17 of the plug body has a flat face for abutment againstthe inner surface of the form panel I. As best illustrated in FIGS. 2and 5, the plug body has a circumferential sealing flange 29 that has aflat face extending in the plane of the flat face of the outer end I7whereby to seal the inside of the plug against entry of concrete at thatend. The circumferential sealing flange 29 is preferably madesufficiently thin to be resilient.

The body of plug 15 is molded with a shoulder 3| along the outer surfacethereof and immediately behind the sealing flange 29. By the provisionof this shoulder 31, the plug I5 molds a recess 33 (FIG. 7) at thelarger end of the face hole. Recess 33 will serve as a seat for aclosing plastic cap 35 that, apart from serving to prevent entry offoreign matter in the fact hole, can be used to give a decorative effectby choosing an appropriate color therefor. Likewise, the circumferentialsealing flange 29 will leave a recess 37 that will tend to increase thedecorative aspect of the face hole as best illustrated in FIG. 9.

The plastic plug I5 of the invention is particularly intended for use ona flat bar 11 formed at one end with a pair of notches 39 (FIG. 2) eachprovided along one of the two edges of the bar 11 and opposite oneanother. A resilient ring 41, preferably made of rubber of circularcross section, has a diameter such as to be pressed into notches 39 andserves to retain plug 15 in position against the inner surface of panelI. Notches 39 and ring 41 are spaced from the end of rod 11 a distancesuch that the plug outer surface 17 and the plug sealing flange 29 maybe slightly pressed, in use, against the inner surface of the formpanel 1. Ring 41 will also prevent the plug 15 from sliding on the rodII, when the panels are assembled, away from the inner surface of panel1.

Reference to FIG. 2 will show that the assembly is extremely simple,ring 41 being first put into position and plug 15 thereafter slid overflat bar 11. With a combination as described, it will be realized thatthe parts can be assembled most simply and there is no danger that theplugs 15 move out of position during the assembly of the other panels orduring pouring and vibrating of the concrete.

Reference will now be made to FIGS. 4, 5 and 6 for the description of atool for use in breaking and removing the end of a flat tie bar afterthe concrete 21 has set and the forms I, 3 have been removed. As will beseen from FIGS. 1 and 5, the ends of the bars 11 project out of theconcrete work 21 after the forms have been removed.

The tool comprises a hollow stem 43 having an inner bore 45 defining alongitudinal inner chamber 47. One end of stem 43 has a transversehandle 49 fixed thereto while the other end has a removing head 51 fixedthereto as by welding. Head 51 has a central shoulder 53 and on one sidethereof a tubular insert S5 integral therewith while a head member 57extends on the other side of shoulder 53 and is also integral therewith.

The head member 57 is outwardly tapered to mate with the tapered bore 25of the plug and is formed with a longitudinal slot 59 properly contouredto slide along the ribs 27, as shown in FIG. 6, and allow passage of thebar 11.

A hammering slug 61 is loosely mounted inside chamber 47.

The aforedescribed tool is used as follows:

The head member 57 of the removing head or mandel 51 is first insertedinto the plug 15, the bar 11 extending through the passage defined bythe slot 59 into the chamber 47 as illustrated in FIG. 5. The handle 49is then rotated back and forth and oscillated to cause breaking of thebar 1 1. This will cause oscillation of the plug 15 because of therectangular opening 18 (FlG. 3) through the transverse wall of thesmaller end 19. The bar 1 1 will then break by the face of the concreteinside of the face hole and become riveted to the wall of the smallerend 19. The tool is then removed, bringing along with it the plug 15.The latter will usually be so tight over the removing head 57 that itcannot be removed by hand. Resort can then be had to the hammering slug61 which can be made to hit the end of bar 1] inside chamber 47. Shouldthese blows be insufficient, as it may sometimes happen, the plug 15 maybe removed by means of a screw driver or the like acting on the sealingflange 27. For this purpose, a groove 63 (FIGS. 4 and S) is formedlongitudinally of the shoulder 53 to allow the screwdriver to reach thesealing flange 29.

It will thus be realized that with the aforedeseribed plastic plug, manyadvantages are obtained as compared to the conventional wooden plug. Inthe first place, the plug can much more easily be put on andparticularly stay on the rod 11. By the provision of the guiding passage23, the plug will not tend to wabble and be displaced during themounting of the forms 1, 3. The presence of rings 41 will furtherenhance the firm positioning of the plug and the more positive abutmentof the sealing flange 29 against the inner face of the panel 1, thusproviding a much greater safety against the inflow of concrete insidethe plug. In other words, the plugs can be placed into position muchmore quickly, will not tend to move out of position during mounting ofthe forms and will provide greater sealing features particularly whenthe concrete is vibrated.

As to the tool for removing the plugs, it will be realized that the plugremoving operation can be done extremely quickly and neatly.

I claim:

1. A plug molded from plastic material and intended for formingapparatus including a flat tie bar of generally rectangular crosssection joining facing panels defining forms for use in making concretewalls or the like, wherein said plug comprises a hollow generallyfrustoconical body having an outer open end intended to be appliedagainst the inner surface of a form panel and having an inner end to beembedded in the concrete of said wall, said inner end being closed by astraight web extending parallel with said outer open end, said bodybeing further provided with guide means for said flat tie bar, theimprovement therewith wherein:

a. said body has a flat annular outer face at said outer end extendinginto a thin annular flexible circumferential sealing flange, said faceintended to seat squarely against the inner surface of a form panelwhereby to seal the inside of said hollow body against entry of concretetherein;

b. said body is formed, exteriorly thereof and immediately behind saidsealing flange, with a cylindrical shoulder intended to define, whensaid plug is removed from the said concrete, a recess for the insertionof a finishing closing cap, said body being further exteriorlyfrustoconical from said shoulder to the inner face thereof;

c. said body is interiorly frustoconical from said outer to said innerends and said guiding means comprise ribs integrally formed with saidbody and extending the full length thereof between said ends radiallyinwardly and diametrically opposite one another, said ribs being furtherformed along the inner faces thereof with right an gular guiding groovesfor the guiding of said flat tie bar. and

d. wherein said inner end straight web has a rectangular openingtherethrough in alignment with said guiding grooves for the passage ofsaid flat tie bar.

2. Apparatus as claimed in claim I in combination with a flat tie barfor holding concrete form panels in position and formed at one end witha pair of notches each provided along one of the two edges of said barand opposite one another, and a resilient ring ofa size to be pressedinto said pair of notches for abutment by said plug from said one end ofsaid bar; said notches and ring being spaced from said end a distancesuch that said plug outer surface and said sealing flange may beslightly pressed, in use, against the inner surface of a form panel.

1. A plug molded from plastic material and intended for formingapparatus including a flat tie bar of generally rectangular crosssection joining facing panels defining forms for use in making concretewalls or the like, wherein said plug comprises a hollow generallyfrustoconical body having an outer open end intended to be appliedagainst the inner surface of a form panel and having an inner end to beembedded in the concrete of said wall, said inner end being closed by astraight web extending parallel with said outer open end, said bodybeing further provided with guide means for said flat tie bar, theimprovement therewith wherein: a. said body has a flat annular outerface at said outer end extending into a thin annular flexiblecircumferential sealing flange, said face intended to seat squarelyagainst the inner surface of a form panel whereby to seal the inside ofsaid hollow body against entry of concrete therein; b. said body isformed, exteriorly thereof and immediately behind said sealing flange,with a cylindrical shoulder intended to define, when said plug isremoved from the said concrete, a recess for the insertion of afinishing closing cap, said body being further exteriorly frustoconicalfrom said shoulder to the inner face thereof; c. said body is interiorlyfrustoconical from said outer to said inner ends and said guiding meanscomprise ribs integrally formed with said body and extending the fulllength thereof between said ends radially inwardly and diametricallyopposite one another, said ribs being further formed along the innerfaces thereof with right angular guiding grooves for the guiding of saidflat tie bar, and d. wherein said inner end straight web has arectangular opening therethrough in alignment with said guiding groovesfor the passage of said flat tie bar.
 2. Apparatus as claimed in claim 1in combination with a flat tie bar for holding concrete form panels inposition and formed at one end with a pair of notches each providedalong one of the two edges of said bar and opposite one another, and aresilient ring of a size to be pressed into said pair of notches forabutment by said plug from said one end of said bar; said notches andring being spaced from said end a distance such that said plug outersurface and said sealing flange may be slightly pressed, in use, againstthe inner surface of a form panel.